Simple Library that finds Dead Code

Here in the company I work, I feel like we have lots of dead code, and I am sure other companies have as well. I looked up for a library that would find them, but the only one I found treat functions that are only called in controllers as unused code. So that doesn’t solve my problem.

I have never written a library in my life and I thought this could be an opportunity to do so. So I found this link (Library Guidelines) to help me get started. So if someone have other articles to share I would appreciate it.

My idea is to get the name of a function and look it up on all the codebase if there is anywhere that has that exactly same name without def before it. In case there isn’t, it means there is a very good chance that this is an unused function. Is it a good idea to do it this way? In which cases this could result in an actually used function?

And now my problem is that I have no idea how to go over all modules and extract its content to a String for example, to be able to check if the function is called there. Could someone point me in a direction on how I could do that?

Thanks!